A fuel injector for direct injection of fuel into the combustion chamber of a mixture-compressing, spark-ignited internal combustion engine which on the downstream end of the fuel injector has a guide and seat area which is formed from three disk-shaped elements is known from German Published Patent Application No. 197 36 682. A swirl element is embedded between a guide element and a valve seat element. The guide element guides an axially movable valve needle penetrating through it, while a valve closing section of the valve needle cooperates with a valve-seat surface of the valve seat element. The swirl element has an inner opening area containing a plurality of swirl channels which are not connected to the outer periphery of the swirl element. The entire opening area extends fully over the axial thickness of the swirl element.
A particular disadvantage of the fuel injector known from the aforementioned document is the fixedly set swirl angle which cannot be adjusted to the different operating conditions of an internal combustion engine, such as partial load and full load operation. As a result, cone opening angle a of the injected mixture cloud also cannot be adjusted to the different operating conditions, which in turn results in inhomogeneities during combustion, increased fuel consumption, as well as increased exhaust gas emission.